An MRI performed on Kratz’s left knee Monday revealed a medial meniscus tear that will need to be repaired surgically. It is unclear when Kratz will have the surgery and a timetable for his recovery will not be known until doctors perform the surgery and survey the damage.

Cincinnati Reds slugger Joey Votto made it back in seven weeks from meniscus surgery last season, but that was considered optimum.

Kratz, 32, injured himself crossing first base in the ninth inning of Saturday night’s game at Milwaukee.

“He felt something pop,” manager Charlie Manuel said.

Kratz is the No. 2 catcher on the Phillies’ depth chart. Carlos Ruiz, the No. 1 catcher, is also on the DL. He suffered a Grade 2 hamstring strain on May 19. The Phillies will not speed up Ruiz’s return because of Kratz’s injury (see story). Ruiz has been doing some running drills and hopes to play in some minor-league rehab games later this week. If all goes well, he could return to the lineup sometime next week.

The Phillies hope Chase Utley, recovering from a strained oblique muscle, will be ready to return next week, as well.

With Ruiz and Kratz out, the Phillies are using Humberto Quintero and Steven Lerud as their catchers (see story).

Kratz has done the bulk of the catching for the Phillies this season as Ruiz had to serve a 25-game suspension at the start of the season for testing positive for a banned stimulant.

In 43 games, Kratz was hitting just .229 but he had eight homers and 22 RBIs. He is second on the team in homers and fourth in RBIs. Kratz had produced well since Ruiz went on the DL. In 17 games, he hit .263 with five homers and 13 RBIs.